xref: /openbmc/linux/net/mac80211/rx.c (revision 22246614)
1 /*
2  * Copyright 2002-2005, Instant802 Networks, Inc.
3  * Copyright 2005-2006, Devicescape Software, Inc.
4  * Copyright 2006-2007	Jiri Benc <jbenc@suse.cz>
5  * Copyright 2007	Johannes Berg <johannes@sipsolutions.net>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 
12 #include <linux/jiffies.h>
13 #include <linux/kernel.h>
14 #include <linux/skbuff.h>
15 #include <linux/netdevice.h>
16 #include <linux/etherdevice.h>
17 #include <linux/rcupdate.h>
18 #include <net/mac80211.h>
19 #include <net/ieee80211_radiotap.h>
20 
21 #include "ieee80211_i.h"
22 #include "led.h"
23 #include "mesh.h"
24 #include "wep.h"
25 #include "wpa.h"
26 #include "tkip.h"
27 #include "wme.h"
28 
29 u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
30 				struct tid_ampdu_rx *tid_agg_rx,
31 				struct sk_buff *skb, u16 mpdu_seq_num,
32 				int bar_req);
33 /*
34  * monitor mode reception
35  *
36  * This function cleans up the SKB, i.e. it removes all the stuff
37  * only useful for monitoring.
38  */
39 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local,
40 					   struct sk_buff *skb,
41 					   int rtap_len)
42 {
43 	skb_pull(skb, rtap_len);
44 
45 	if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
46 		if (likely(skb->len > FCS_LEN))
47 			skb_trim(skb, skb->len - FCS_LEN);
48 		else {
49 			/* driver bug */
50 			WARN_ON(1);
51 			dev_kfree_skb(skb);
52 			skb = NULL;
53 		}
54 	}
55 
56 	return skb;
57 }
58 
59 static inline int should_drop_frame(struct ieee80211_rx_status *status,
60 				    struct sk_buff *skb,
61 				    int present_fcs_len,
62 				    int radiotap_len)
63 {
64 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
65 
66 	if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
67 		return 1;
68 	if (unlikely(skb->len < 16 + present_fcs_len + radiotap_len))
69 		return 1;
70 	if (((hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_FTYPE)) ==
71 			cpu_to_le16(IEEE80211_FTYPE_CTL)) &&
72 	    ((hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE)) !=
73 			cpu_to_le16(IEEE80211_STYPE_PSPOLL)) &&
74 	    ((hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE)) !=
75 			cpu_to_le16(IEEE80211_STYPE_BACK_REQ)))
76 		return 1;
77 	return 0;
78 }
79 
80 /*
81  * This function copies a received frame to all monitor interfaces and
82  * returns a cleaned-up SKB that no longer includes the FCS nor the
83  * radiotap header the driver might have added.
84  */
85 static struct sk_buff *
86 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
87 		     struct ieee80211_rx_status *status,
88 		     struct ieee80211_rate *rate)
89 {
90 	struct ieee80211_sub_if_data *sdata;
91 	int needed_headroom = 0;
92 	struct ieee80211_radiotap_header *rthdr;
93 	__le64 *rttsft = NULL;
94 	struct ieee80211_rtap_fixed_data {
95 		u8 flags;
96 		u8 rate;
97 		__le16 chan_freq;
98 		__le16 chan_flags;
99 		u8 antsignal;
100 		u8 padding_for_rxflags;
101 		__le16 rx_flags;
102 	} __attribute__ ((packed)) *rtfixed;
103 	struct sk_buff *skb, *skb2;
104 	struct net_device *prev_dev = NULL;
105 	int present_fcs_len = 0;
106 	int rtap_len = 0;
107 
108 	/*
109 	 * First, we may need to make a copy of the skb because
110 	 *  (1) we need to modify it for radiotap (if not present), and
111 	 *  (2) the other RX handlers will modify the skb we got.
112 	 *
113 	 * We don't need to, of course, if we aren't going to return
114 	 * the SKB because it has a bad FCS/PLCP checksum.
115 	 */
116 	if (status->flag & RX_FLAG_RADIOTAP)
117 		rtap_len = ieee80211_get_radiotap_len(origskb->data);
118 	else
119 		/* room for radiotap header, always present fields and TSFT */
120 		needed_headroom = sizeof(*rthdr) + sizeof(*rtfixed) + 8;
121 
122 	if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
123 		present_fcs_len = FCS_LEN;
124 
125 	if (!local->monitors) {
126 		if (should_drop_frame(status, origskb, present_fcs_len,
127 				      rtap_len)) {
128 			dev_kfree_skb(origskb);
129 			return NULL;
130 		}
131 
132 		return remove_monitor_info(local, origskb, rtap_len);
133 	}
134 
135 	if (should_drop_frame(status, origskb, present_fcs_len, rtap_len)) {
136 		/* only need to expand headroom if necessary */
137 		skb = origskb;
138 		origskb = NULL;
139 
140 		/*
141 		 * This shouldn't trigger often because most devices have an
142 		 * RX header they pull before we get here, and that should
143 		 * be big enough for our radiotap information. We should
144 		 * probably export the length to drivers so that we can have
145 		 * them allocate enough headroom to start with.
146 		 */
147 		if (skb_headroom(skb) < needed_headroom &&
148 		    pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
149 			dev_kfree_skb(skb);
150 			return NULL;
151 		}
152 	} else {
153 		/*
154 		 * Need to make a copy and possibly remove radiotap header
155 		 * and FCS from the original.
156 		 */
157 		skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
158 
159 		origskb = remove_monitor_info(local, origskb, rtap_len);
160 
161 		if (!skb)
162 			return origskb;
163 	}
164 
165 	/* if necessary, prepend radiotap information */
166 	if (!(status->flag & RX_FLAG_RADIOTAP)) {
167 		rtfixed = (void *) skb_push(skb, sizeof(*rtfixed));
168 		rtap_len = sizeof(*rthdr) + sizeof(*rtfixed);
169 		if (status->flag & RX_FLAG_TSFT) {
170 			rttsft = (void *) skb_push(skb, sizeof(*rttsft));
171 			rtap_len += 8;
172 		}
173 		rthdr = (void *) skb_push(skb, sizeof(*rthdr));
174 		memset(rthdr, 0, sizeof(*rthdr));
175 		memset(rtfixed, 0, sizeof(*rtfixed));
176 		rthdr->it_present =
177 			cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
178 				    (1 << IEEE80211_RADIOTAP_RATE) |
179 				    (1 << IEEE80211_RADIOTAP_CHANNEL) |
180 				    (1 << IEEE80211_RADIOTAP_DB_ANTSIGNAL) |
181 				    (1 << IEEE80211_RADIOTAP_RX_FLAGS));
182 		rtfixed->flags = 0;
183 		if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
184 			rtfixed->flags |= IEEE80211_RADIOTAP_F_FCS;
185 
186 		if (rttsft) {
187 			*rttsft = cpu_to_le64(status->mactime);
188 			rthdr->it_present |=
189 				cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
190 		}
191 
192 		/* FIXME: when radiotap gets a 'bad PLCP' flag use it here */
193 		rtfixed->rx_flags = 0;
194 		if (status->flag &
195 		    (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
196 			rtfixed->rx_flags |=
197 				cpu_to_le16(IEEE80211_RADIOTAP_F_RX_BADFCS);
198 
199 		rtfixed->rate = rate->bitrate / 5;
200 
201 		rtfixed->chan_freq = cpu_to_le16(status->freq);
202 
203 		if (status->band == IEEE80211_BAND_5GHZ)
204 			rtfixed->chan_flags =
205 				cpu_to_le16(IEEE80211_CHAN_OFDM |
206 					    IEEE80211_CHAN_5GHZ);
207 		else
208 			rtfixed->chan_flags =
209 				cpu_to_le16(IEEE80211_CHAN_DYN |
210 					    IEEE80211_CHAN_2GHZ);
211 
212 		rtfixed->antsignal = status->ssi;
213 		rthdr->it_len = cpu_to_le16(rtap_len);
214 	}
215 
216 	skb_reset_mac_header(skb);
217 	skb->ip_summed = CHECKSUM_UNNECESSARY;
218 	skb->pkt_type = PACKET_OTHERHOST;
219 	skb->protocol = htons(ETH_P_802_2);
220 
221 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
222 		if (!netif_running(sdata->dev))
223 			continue;
224 
225 		if (sdata->vif.type != IEEE80211_IF_TYPE_MNTR)
226 			continue;
227 
228 		if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
229 			continue;
230 
231 		if (prev_dev) {
232 			skb2 = skb_clone(skb, GFP_ATOMIC);
233 			if (skb2) {
234 				skb2->dev = prev_dev;
235 				netif_rx(skb2);
236 			}
237 		}
238 
239 		prev_dev = sdata->dev;
240 		sdata->dev->stats.rx_packets++;
241 		sdata->dev->stats.rx_bytes += skb->len;
242 	}
243 
244 	if (prev_dev) {
245 		skb->dev = prev_dev;
246 		netif_rx(skb);
247 	} else
248 		dev_kfree_skb(skb);
249 
250 	return origskb;
251 }
252 
253 
254 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
255 {
256 	u8 *data = rx->skb->data;
257 	int tid;
258 
259 	/* does the frame have a qos control field? */
260 	if (WLAN_FC_IS_QOS_DATA(rx->fc)) {
261 		u8 *qc = data + ieee80211_get_hdrlen(rx->fc) - QOS_CONTROL_LEN;
262 		/* frame has qos control */
263 		tid = qc[0] & QOS_CONTROL_TID_MASK;
264 		if (qc[0] & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT)
265 			rx->flags |= IEEE80211_RX_AMSDU;
266 		else
267 			rx->flags &= ~IEEE80211_RX_AMSDU;
268 	} else {
269 		if (unlikely((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_MGMT)) {
270 			/* Separate TID for management frames */
271 			tid = NUM_RX_DATA_QUEUES - 1;
272 		} else {
273 			/* no qos control present */
274 			tid = 0; /* 802.1d - Best Effort */
275 		}
276 	}
277 
278 	I802_DEBUG_INC(rx->local->wme_rx_queue[tid]);
279 	/* only a debug counter, sta might not be assigned properly yet */
280 	if (rx->sta)
281 		I802_DEBUG_INC(rx->sta->wme_rx_queue[tid]);
282 
283 	rx->queue = tid;
284 	/* Set skb->priority to 1d tag if highest order bit of TID is not set.
285 	 * For now, set skb->priority to 0 for other cases. */
286 	rx->skb->priority = (tid > 7) ? 0 : tid;
287 }
288 
289 static void ieee80211_verify_ip_alignment(struct ieee80211_rx_data *rx)
290 {
291 #ifdef CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT
292 	int hdrlen;
293 
294 	if (!WLAN_FC_DATA_PRESENT(rx->fc))
295 		return;
296 
297 	/*
298 	 * Drivers are required to align the payload data in a way that
299 	 * guarantees that the contained IP header is aligned to a four-
300 	 * byte boundary. In the case of regular frames, this simply means
301 	 * aligning the payload to a four-byte boundary (because either
302 	 * the IP header is directly contained, or IV/RFC1042 headers that
303 	 * have a length divisible by four are in front of it.
304 	 *
305 	 * With A-MSDU frames, however, the payload data address must
306 	 * yield two modulo four because there are 14-byte 802.3 headers
307 	 * within the A-MSDU frames that push the IP header further back
308 	 * to a multiple of four again. Thankfully, the specs were sane
309 	 * enough this time around to require padding each A-MSDU subframe
310 	 * to a length that is a multiple of four.
311 	 *
312 	 * Padding like atheros hardware adds which is inbetween the 802.11
313 	 * header and the payload is not supported, the driver is required
314 	 * to move the 802.11 header further back in that case.
315 	 */
316 	hdrlen = ieee80211_get_hdrlen(rx->fc);
317 	if (rx->flags & IEEE80211_RX_AMSDU)
318 		hdrlen += ETH_HLEN;
319 	WARN_ON_ONCE(((unsigned long)(rx->skb->data + hdrlen)) & 3);
320 #endif
321 }
322 
323 
324 static u32 ieee80211_rx_load_stats(struct ieee80211_local *local,
325 				   struct sk_buff *skb,
326 				   struct ieee80211_rx_status *status,
327 				   struct ieee80211_rate *rate)
328 {
329 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
330 	u32 load = 0, hdrtime;
331 
332 	/* Estimate total channel use caused by this frame */
333 
334 	/* 1 bit at 1 Mbit/s takes 1 usec; in channel_use values,
335 	 * 1 usec = 1/8 * (1080 / 10) = 13.5 */
336 
337 	if (status->band == IEEE80211_BAND_5GHZ ||
338 	    (status->band == IEEE80211_BAND_5GHZ &&
339 	     rate->flags & IEEE80211_RATE_ERP_G))
340 		hdrtime = CHAN_UTIL_HDR_SHORT;
341 	else
342 		hdrtime = CHAN_UTIL_HDR_LONG;
343 
344 	load = hdrtime;
345 	if (!is_multicast_ether_addr(hdr->addr1))
346 		load += hdrtime;
347 
348 	/* TODO: optimise again */
349 	load += skb->len * CHAN_UTIL_RATE_LCM / rate->bitrate;
350 
351 	/* Divide channel_use by 8 to avoid wrapping around the counter */
352 	load >>= CHAN_UTIL_SHIFT;
353 
354 	return load;
355 }
356 
357 /* rx handlers */
358 
359 static ieee80211_rx_result
360 ieee80211_rx_h_if_stats(struct ieee80211_rx_data *rx)
361 {
362 	if (rx->sta)
363 		rx->sta->channel_use_raw += rx->load;
364 	rx->sdata->channel_use_raw += rx->load;
365 	return RX_CONTINUE;
366 }
367 
368 static ieee80211_rx_result
369 ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx)
370 {
371 	struct ieee80211_local *local = rx->local;
372 	struct sk_buff *skb = rx->skb;
373 
374 	if (unlikely(local->sta_hw_scanning))
375 		return ieee80211_sta_rx_scan(rx->dev, skb, rx->status);
376 
377 	if (unlikely(local->sta_sw_scanning)) {
378 		/* drop all the other packets during a software scan anyway */
379 		if (ieee80211_sta_rx_scan(rx->dev, skb, rx->status)
380 		    != RX_QUEUED)
381 			dev_kfree_skb(skb);
382 		return RX_QUEUED;
383 	}
384 
385 	if (unlikely(rx->flags & IEEE80211_RX_IN_SCAN)) {
386 		/* scanning finished during invoking of handlers */
387 		I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
388 		return RX_DROP_UNUSABLE;
389 	}
390 
391 	return RX_CONTINUE;
392 }
393 
394 static ieee80211_rx_result
395 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
396 {
397 	int hdrlen = ieee80211_get_hdrlen(rx->fc);
398 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
399 
400 #define msh_h_get(h, l) ((struct ieee80211s_hdr *) ((u8 *)h + l))
401 
402 	if ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA) {
403 		if (!((rx->fc & IEEE80211_FCTL_FROMDS) &&
404 		      (rx->fc & IEEE80211_FCTL_TODS)))
405 			return RX_DROP_MONITOR;
406 		if (memcmp(hdr->addr4, rx->dev->dev_addr, ETH_ALEN) == 0)
407 			return RX_DROP_MONITOR;
408 	}
409 
410 	/* If there is not an established peer link and this is not a peer link
411 	 * establisment frame, beacon or probe, drop the frame.
412 	 */
413 
414 	if (!rx->sta || sta_plink_state(rx->sta) != PLINK_ESTAB) {
415 		struct ieee80211_mgmt *mgmt;
416 
417 		if ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT)
418 			return RX_DROP_MONITOR;
419 
420 		switch (rx->fc & IEEE80211_FCTL_STYPE) {
421 		case IEEE80211_STYPE_ACTION:
422 			mgmt = (struct ieee80211_mgmt *)hdr;
423 			if (mgmt->u.action.category != PLINK_CATEGORY)
424 				return RX_DROP_MONITOR;
425 			/* fall through on else */
426 		case IEEE80211_STYPE_PROBE_REQ:
427 		case IEEE80211_STYPE_PROBE_RESP:
428 		case IEEE80211_STYPE_BEACON:
429 			return RX_CONTINUE;
430 			break;
431 		default:
432 			return RX_DROP_MONITOR;
433 		}
434 
435 	 } else if ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
436 		    is_multicast_ether_addr(hdr->addr1) &&
437 		    mesh_rmc_check(hdr->addr4, msh_h_get(hdr, hdrlen), rx->dev))
438 		return RX_DROP_MONITOR;
439 #undef msh_h_get
440 
441 	return RX_CONTINUE;
442 }
443 
444 
445 static ieee80211_rx_result
446 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
447 {
448 	struct ieee80211_hdr *hdr;
449 
450 	hdr = (struct ieee80211_hdr *) rx->skb->data;
451 
452 	/* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
453 	if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
454 		if (unlikely(rx->fc & IEEE80211_FCTL_RETRY &&
455 			     rx->sta->last_seq_ctrl[rx->queue] ==
456 			     hdr->seq_ctrl)) {
457 			if (rx->flags & IEEE80211_RX_RA_MATCH) {
458 				rx->local->dot11FrameDuplicateCount++;
459 				rx->sta->num_duplicates++;
460 			}
461 			return RX_DROP_MONITOR;
462 		} else
463 			rx->sta->last_seq_ctrl[rx->queue] = hdr->seq_ctrl;
464 	}
465 
466 	if (unlikely(rx->skb->len < 16)) {
467 		I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
468 		return RX_DROP_MONITOR;
469 	}
470 
471 	/* Drop disallowed frame classes based on STA auth/assoc state;
472 	 * IEEE 802.11, Chap 5.5.
473 	 *
474 	 * 80211.o does filtering only based on association state, i.e., it
475 	 * drops Class 3 frames from not associated stations. hostapd sends
476 	 * deauth/disassoc frames when needed. In addition, hostapd is
477 	 * responsible for filtering on both auth and assoc states.
478 	 */
479 
480 	if (ieee80211_vif_is_mesh(&rx->sdata->vif))
481 		return ieee80211_rx_mesh_check(rx);
482 
483 	if (unlikely(((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA ||
484 		      ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_CTL &&
485 		       (rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_PSPOLL)) &&
486 		     rx->sdata->vif.type != IEEE80211_IF_TYPE_IBSS &&
487 		     (!rx->sta || !(rx->sta->flags & WLAN_STA_ASSOC)))) {
488 		if ((!(rx->fc & IEEE80211_FCTL_FROMDS) &&
489 		     !(rx->fc & IEEE80211_FCTL_TODS) &&
490 		     (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA)
491 		    || !(rx->flags & IEEE80211_RX_RA_MATCH)) {
492 			/* Drop IBSS frames and frames for other hosts
493 			 * silently. */
494 			return RX_DROP_MONITOR;
495 		}
496 
497 		return RX_DROP_MONITOR;
498 	}
499 
500 	return RX_CONTINUE;
501 }
502 
503 
504 static ieee80211_rx_result
505 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
506 {
507 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
508 	int keyidx;
509 	int hdrlen;
510 	ieee80211_rx_result result = RX_DROP_UNUSABLE;
511 	struct ieee80211_key *stakey = NULL;
512 
513 	/*
514 	 * Key selection 101
515 	 *
516 	 * There are three types of keys:
517 	 *  - GTK (group keys)
518 	 *  - PTK (pairwise keys)
519 	 *  - STK (station-to-station pairwise keys)
520 	 *
521 	 * When selecting a key, we have to distinguish between multicast
522 	 * (including broadcast) and unicast frames, the latter can only
523 	 * use PTKs and STKs while the former always use GTKs. Unless, of
524 	 * course, actual WEP keys ("pre-RSNA") are used, then unicast
525 	 * frames can also use key indizes like GTKs. Hence, if we don't
526 	 * have a PTK/STK we check the key index for a WEP key.
527 	 *
528 	 * Note that in a regular BSS, multicast frames are sent by the
529 	 * AP only, associated stations unicast the frame to the AP first
530 	 * which then multicasts it on their behalf.
531 	 *
532 	 * There is also a slight problem in IBSS mode: GTKs are negotiated
533 	 * with each station, that is something we don't currently handle.
534 	 * The spec seems to expect that one negotiates the same key with
535 	 * every station but there's no such requirement; VLANs could be
536 	 * possible.
537 	 */
538 
539 	if (!(rx->fc & IEEE80211_FCTL_PROTECTED))
540 		return RX_CONTINUE;
541 
542 	/*
543 	 * No point in finding a key and decrypting if the frame is neither
544 	 * addressed to us nor a multicast frame.
545 	 */
546 	if (!(rx->flags & IEEE80211_RX_RA_MATCH))
547 		return RX_CONTINUE;
548 
549 	if (rx->sta)
550 		stakey = rcu_dereference(rx->sta->key);
551 
552 	if (!is_multicast_ether_addr(hdr->addr1) && stakey) {
553 		rx->key = stakey;
554 	} else {
555 		/*
556 		 * The device doesn't give us the IV so we won't be
557 		 * able to look up the key. That's ok though, we
558 		 * don't need to decrypt the frame, we just won't
559 		 * be able to keep statistics accurate.
560 		 * Except for key threshold notifications, should
561 		 * we somehow allow the driver to tell us which key
562 		 * the hardware used if this flag is set?
563 		 */
564 		if ((rx->status->flag & RX_FLAG_DECRYPTED) &&
565 		    (rx->status->flag & RX_FLAG_IV_STRIPPED))
566 			return RX_CONTINUE;
567 
568 		hdrlen = ieee80211_get_hdrlen(rx->fc);
569 
570 		if (rx->skb->len < 8 + hdrlen)
571 			return RX_DROP_UNUSABLE; /* TODO: count this? */
572 
573 		/*
574 		 * no need to call ieee80211_wep_get_keyidx,
575 		 * it verifies a bunch of things we've done already
576 		 */
577 		keyidx = rx->skb->data[hdrlen + 3] >> 6;
578 
579 		rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
580 
581 		/*
582 		 * RSNA-protected unicast frames should always be sent with
583 		 * pairwise or station-to-station keys, but for WEP we allow
584 		 * using a key index as well.
585 		 */
586 		if (rx->key && rx->key->conf.alg != ALG_WEP &&
587 		    !is_multicast_ether_addr(hdr->addr1))
588 			rx->key = NULL;
589 	}
590 
591 	if (rx->key) {
592 		rx->key->tx_rx_count++;
593 		/* TODO: add threshold stuff again */
594 	} else {
595 #ifdef CONFIG_MAC80211_DEBUG
596 		if (net_ratelimit())
597 			printk(KERN_DEBUG "%s: RX protected frame,"
598 			       " but have no key\n", rx->dev->name);
599 #endif /* CONFIG_MAC80211_DEBUG */
600 		return RX_DROP_MONITOR;
601 	}
602 
603 	/* Check for weak IVs if possible */
604 	if (rx->sta && rx->key->conf.alg == ALG_WEP &&
605 	    ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA) &&
606 	    (!(rx->status->flag & RX_FLAG_IV_STRIPPED) ||
607 	     !(rx->status->flag & RX_FLAG_DECRYPTED)) &&
608 	    ieee80211_wep_is_weak_iv(rx->skb, rx->key))
609 		rx->sta->wep_weak_iv_count++;
610 
611 	switch (rx->key->conf.alg) {
612 	case ALG_WEP:
613 		result = ieee80211_crypto_wep_decrypt(rx);
614 		break;
615 	case ALG_TKIP:
616 		result = ieee80211_crypto_tkip_decrypt(rx);
617 		break;
618 	case ALG_CCMP:
619 		result = ieee80211_crypto_ccmp_decrypt(rx);
620 		break;
621 	}
622 
623 	/* either the frame has been decrypted or will be dropped */
624 	rx->status->flag |= RX_FLAG_DECRYPTED;
625 
626 	return result;
627 }
628 
629 static void ap_sta_ps_start(struct net_device *dev, struct sta_info *sta)
630 {
631 	struct ieee80211_sub_if_data *sdata;
632 	DECLARE_MAC_BUF(mac);
633 
634 	sdata = sta->sdata;
635 
636 	if (sdata->bss)
637 		atomic_inc(&sdata->bss->num_sta_ps);
638 	sta->flags |= WLAN_STA_PS;
639 	sta->flags &= ~WLAN_STA_PSPOLL;
640 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
641 	printk(KERN_DEBUG "%s: STA %s aid %d enters power save mode\n",
642 	       dev->name, print_mac(mac, sta->addr), sta->aid);
643 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
644 }
645 
646 static int ap_sta_ps_end(struct net_device *dev, struct sta_info *sta)
647 {
648 	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
649 	struct sk_buff *skb;
650 	int sent = 0;
651 	struct ieee80211_sub_if_data *sdata;
652 	struct ieee80211_tx_packet_data *pkt_data;
653 	DECLARE_MAC_BUF(mac);
654 
655 	sdata = sta->sdata;
656 
657 	if (sdata->bss)
658 		atomic_dec(&sdata->bss->num_sta_ps);
659 
660 	sta->flags &= ~(WLAN_STA_PS | WLAN_STA_PSPOLL);
661 
662 	if (!skb_queue_empty(&sta->ps_tx_buf))
663 		sta_info_clear_tim_bit(sta);
664 
665 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
666 	printk(KERN_DEBUG "%s: STA %s aid %d exits power save mode\n",
667 	       dev->name, print_mac(mac, sta->addr), sta->aid);
668 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
669 
670 	/* Send all buffered frames to the station */
671 	while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) {
672 		pkt_data = (struct ieee80211_tx_packet_data *) skb->cb;
673 		sent++;
674 		pkt_data->flags |= IEEE80211_TXPD_REQUEUE;
675 		dev_queue_xmit(skb);
676 	}
677 	while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) {
678 		pkt_data = (struct ieee80211_tx_packet_data *) skb->cb;
679 		local->total_ps_buffered--;
680 		sent++;
681 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
682 		printk(KERN_DEBUG "%s: STA %s aid %d send PS frame "
683 		       "since STA not sleeping anymore\n", dev->name,
684 		       print_mac(mac, sta->addr), sta->aid);
685 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
686 		pkt_data->flags |= IEEE80211_TXPD_REQUEUE;
687 		dev_queue_xmit(skb);
688 	}
689 
690 	return sent;
691 }
692 
693 static ieee80211_rx_result
694 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
695 {
696 	struct sta_info *sta = rx->sta;
697 	struct net_device *dev = rx->dev;
698 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
699 
700 	if (!sta)
701 		return RX_CONTINUE;
702 
703 	/* Update last_rx only for IBSS packets which are for the current
704 	 * BSSID to avoid keeping the current IBSS network alive in cases where
705 	 * other STAs are using different BSSID. */
706 	if (rx->sdata->vif.type == IEEE80211_IF_TYPE_IBSS) {
707 		u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
708 						IEEE80211_IF_TYPE_IBSS);
709 		if (compare_ether_addr(bssid, rx->sdata->u.sta.bssid) == 0)
710 			sta->last_rx = jiffies;
711 	} else
712 	if (!is_multicast_ether_addr(hdr->addr1) ||
713 	    rx->sdata->vif.type == IEEE80211_IF_TYPE_STA) {
714 		/* Update last_rx only for unicast frames in order to prevent
715 		 * the Probe Request frames (the only broadcast frames from a
716 		 * STA in infrastructure mode) from keeping a connection alive.
717 		 * Mesh beacons will update last_rx when if they are found to
718 		 * match the current local configuration when processed.
719 		 */
720 		sta->last_rx = jiffies;
721 	}
722 
723 	if (!(rx->flags & IEEE80211_RX_RA_MATCH))
724 		return RX_CONTINUE;
725 
726 	sta->rx_fragments++;
727 	sta->rx_bytes += rx->skb->len;
728 	sta->last_rssi = rx->status->ssi;
729 	sta->last_signal = rx->status->signal;
730 	sta->last_noise = rx->status->noise;
731 
732 	if (!(rx->fc & IEEE80211_FCTL_MOREFRAGS)) {
733 		/* Change STA power saving mode only in the end of a frame
734 		 * exchange sequence */
735 		if ((sta->flags & WLAN_STA_PS) && !(rx->fc & IEEE80211_FCTL_PM))
736 			rx->sent_ps_buffered += ap_sta_ps_end(dev, sta);
737 		else if (!(sta->flags & WLAN_STA_PS) &&
738 			 (rx->fc & IEEE80211_FCTL_PM))
739 			ap_sta_ps_start(dev, sta);
740 	}
741 
742 	/* Drop data::nullfunc frames silently, since they are used only to
743 	 * control station power saving mode. */
744 	if ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
745 	    (rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_NULLFUNC) {
746 		I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
747 		/* Update counter and free packet here to avoid counting this
748 		 * as a dropped packed. */
749 		sta->rx_packets++;
750 		dev_kfree_skb(rx->skb);
751 		return RX_QUEUED;
752 	}
753 
754 	return RX_CONTINUE;
755 } /* ieee80211_rx_h_sta_process */
756 
757 static inline struct ieee80211_fragment_entry *
758 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
759 			 unsigned int frag, unsigned int seq, int rx_queue,
760 			 struct sk_buff **skb)
761 {
762 	struct ieee80211_fragment_entry *entry;
763 	int idx;
764 
765 	idx = sdata->fragment_next;
766 	entry = &sdata->fragments[sdata->fragment_next++];
767 	if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
768 		sdata->fragment_next = 0;
769 
770 	if (!skb_queue_empty(&entry->skb_list)) {
771 #ifdef CONFIG_MAC80211_DEBUG
772 		struct ieee80211_hdr *hdr =
773 			(struct ieee80211_hdr *) entry->skb_list.next->data;
774 		DECLARE_MAC_BUF(mac);
775 		DECLARE_MAC_BUF(mac2);
776 		printk(KERN_DEBUG "%s: RX reassembly removed oldest "
777 		       "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
778 		       "addr1=%s addr2=%s\n",
779 		       sdata->dev->name, idx,
780 		       jiffies - entry->first_frag_time, entry->seq,
781 		       entry->last_frag, print_mac(mac, hdr->addr1),
782 		       print_mac(mac2, hdr->addr2));
783 #endif /* CONFIG_MAC80211_DEBUG */
784 		__skb_queue_purge(&entry->skb_list);
785 	}
786 
787 	__skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
788 	*skb = NULL;
789 	entry->first_frag_time = jiffies;
790 	entry->seq = seq;
791 	entry->rx_queue = rx_queue;
792 	entry->last_frag = frag;
793 	entry->ccmp = 0;
794 	entry->extra_len = 0;
795 
796 	return entry;
797 }
798 
799 static inline struct ieee80211_fragment_entry *
800 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
801 			  u16 fc, unsigned int frag, unsigned int seq,
802 			  int rx_queue, struct ieee80211_hdr *hdr)
803 {
804 	struct ieee80211_fragment_entry *entry;
805 	int i, idx;
806 
807 	idx = sdata->fragment_next;
808 	for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
809 		struct ieee80211_hdr *f_hdr;
810 		u16 f_fc;
811 
812 		idx--;
813 		if (idx < 0)
814 			idx = IEEE80211_FRAGMENT_MAX - 1;
815 
816 		entry = &sdata->fragments[idx];
817 		if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
818 		    entry->rx_queue != rx_queue ||
819 		    entry->last_frag + 1 != frag)
820 			continue;
821 
822 		f_hdr = (struct ieee80211_hdr *) entry->skb_list.next->data;
823 		f_fc = le16_to_cpu(f_hdr->frame_control);
824 
825 		if ((fc & IEEE80211_FCTL_FTYPE) != (f_fc & IEEE80211_FCTL_FTYPE) ||
826 		    compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
827 		    compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
828 			continue;
829 
830 		if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
831 			__skb_queue_purge(&entry->skb_list);
832 			continue;
833 		}
834 		return entry;
835 	}
836 
837 	return NULL;
838 }
839 
840 static ieee80211_rx_result
841 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
842 {
843 	struct ieee80211_hdr *hdr;
844 	u16 sc;
845 	unsigned int frag, seq;
846 	struct ieee80211_fragment_entry *entry;
847 	struct sk_buff *skb;
848 	DECLARE_MAC_BUF(mac);
849 
850 	hdr = (struct ieee80211_hdr *) rx->skb->data;
851 	sc = le16_to_cpu(hdr->seq_ctrl);
852 	frag = sc & IEEE80211_SCTL_FRAG;
853 
854 	if (likely((!(rx->fc & IEEE80211_FCTL_MOREFRAGS) && frag == 0) ||
855 		   (rx->skb)->len < 24 ||
856 		   is_multicast_ether_addr(hdr->addr1))) {
857 		/* not fragmented */
858 		goto out;
859 	}
860 	I802_DEBUG_INC(rx->local->rx_handlers_fragments);
861 
862 	seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
863 
864 	if (frag == 0) {
865 		/* This is the first fragment of a new frame. */
866 		entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
867 						 rx->queue, &(rx->skb));
868 		if (rx->key && rx->key->conf.alg == ALG_CCMP &&
869 		    (rx->fc & IEEE80211_FCTL_PROTECTED)) {
870 			/* Store CCMP PN so that we can verify that the next
871 			 * fragment has a sequential PN value. */
872 			entry->ccmp = 1;
873 			memcpy(entry->last_pn,
874 			       rx->key->u.ccmp.rx_pn[rx->queue],
875 			       CCMP_PN_LEN);
876 		}
877 		return RX_QUEUED;
878 	}
879 
880 	/* This is a fragment for a frame that should already be pending in
881 	 * fragment cache. Add this fragment to the end of the pending entry.
882 	 */
883 	entry = ieee80211_reassemble_find(rx->sdata, rx->fc, frag, seq,
884 					  rx->queue, hdr);
885 	if (!entry) {
886 		I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
887 		return RX_DROP_MONITOR;
888 	}
889 
890 	/* Verify that MPDUs within one MSDU have sequential PN values.
891 	 * (IEEE 802.11i, 8.3.3.4.5) */
892 	if (entry->ccmp) {
893 		int i;
894 		u8 pn[CCMP_PN_LEN], *rpn;
895 		if (!rx->key || rx->key->conf.alg != ALG_CCMP)
896 			return RX_DROP_UNUSABLE;
897 		memcpy(pn, entry->last_pn, CCMP_PN_LEN);
898 		for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
899 			pn[i]++;
900 			if (pn[i])
901 				break;
902 		}
903 		rpn = rx->key->u.ccmp.rx_pn[rx->queue];
904 		if (memcmp(pn, rpn, CCMP_PN_LEN) != 0) {
905 			if (net_ratelimit())
906 				printk(KERN_DEBUG "%s: defrag: CCMP PN not "
907 				       "sequential A2=%s"
908 				       " PN=%02x%02x%02x%02x%02x%02x "
909 				       "(expected %02x%02x%02x%02x%02x%02x)\n",
910 				       rx->dev->name, print_mac(mac, hdr->addr2),
911 				       rpn[0], rpn[1], rpn[2], rpn[3], rpn[4],
912 				       rpn[5], pn[0], pn[1], pn[2], pn[3],
913 				       pn[4], pn[5]);
914 			return RX_DROP_UNUSABLE;
915 		}
916 		memcpy(entry->last_pn, pn, CCMP_PN_LEN);
917 	}
918 
919 	skb_pull(rx->skb, ieee80211_get_hdrlen(rx->fc));
920 	__skb_queue_tail(&entry->skb_list, rx->skb);
921 	entry->last_frag = frag;
922 	entry->extra_len += rx->skb->len;
923 	if (rx->fc & IEEE80211_FCTL_MOREFRAGS) {
924 		rx->skb = NULL;
925 		return RX_QUEUED;
926 	}
927 
928 	rx->skb = __skb_dequeue(&entry->skb_list);
929 	if (skb_tailroom(rx->skb) < entry->extra_len) {
930 		I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
931 		if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
932 					      GFP_ATOMIC))) {
933 			I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
934 			__skb_queue_purge(&entry->skb_list);
935 			return RX_DROP_UNUSABLE;
936 		}
937 	}
938 	while ((skb = __skb_dequeue(&entry->skb_list))) {
939 		memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
940 		dev_kfree_skb(skb);
941 	}
942 
943 	/* Complete frame has been reassembled - process it now */
944 	rx->flags |= IEEE80211_RX_FRAGMENTED;
945 
946  out:
947 	if (rx->sta)
948 		rx->sta->rx_packets++;
949 	if (is_multicast_ether_addr(hdr->addr1))
950 		rx->local->dot11MulticastReceivedFrameCount++;
951 	else
952 		ieee80211_led_rx(rx->local);
953 	return RX_CONTINUE;
954 }
955 
956 static ieee80211_rx_result
957 ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx)
958 {
959 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
960 	struct sk_buff *skb;
961 	int no_pending_pkts;
962 	DECLARE_MAC_BUF(mac);
963 
964 	if (likely(!rx->sta ||
965 		   (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_CTL ||
966 		   (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_PSPOLL ||
967 		   !(rx->flags & IEEE80211_RX_RA_MATCH)))
968 		return RX_CONTINUE;
969 
970 	if ((sdata->vif.type != IEEE80211_IF_TYPE_AP) &&
971 	    (sdata->vif.type != IEEE80211_IF_TYPE_VLAN))
972 		return RX_DROP_UNUSABLE;
973 
974 	skb = skb_dequeue(&rx->sta->tx_filtered);
975 	if (!skb) {
976 		skb = skb_dequeue(&rx->sta->ps_tx_buf);
977 		if (skb)
978 			rx->local->total_ps_buffered--;
979 	}
980 	no_pending_pkts = skb_queue_empty(&rx->sta->tx_filtered) &&
981 		skb_queue_empty(&rx->sta->ps_tx_buf);
982 
983 	if (skb) {
984 		struct ieee80211_hdr *hdr =
985 			(struct ieee80211_hdr *) skb->data;
986 
987 		/*
988 		 * Tell TX path to send one frame even though the STA may
989 		 * still remain is PS mode after this frame exchange.
990 		 */
991 		rx->sta->flags |= WLAN_STA_PSPOLL;
992 
993 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
994 		printk(KERN_DEBUG "STA %s aid %d: PS Poll (entries after %d)\n",
995 		       print_mac(mac, rx->sta->addr), rx->sta->aid,
996 		       skb_queue_len(&rx->sta->ps_tx_buf));
997 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
998 
999 		/* Use MoreData flag to indicate whether there are more
1000 		 * buffered frames for this STA */
1001 		if (no_pending_pkts)
1002 			hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
1003 		else
1004 			hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
1005 
1006 		dev_queue_xmit(skb);
1007 
1008 		if (no_pending_pkts)
1009 			sta_info_clear_tim_bit(rx->sta);
1010 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1011 	} else if (!rx->sent_ps_buffered) {
1012 		/*
1013 		 * FIXME: This can be the result of a race condition between
1014 		 *	  us expiring a frame and the station polling for it.
1015 		 *	  Should we send it a null-func frame indicating we
1016 		 *	  have nothing buffered for it?
1017 		 */
1018 		printk(KERN_DEBUG "%s: STA %s sent PS Poll even "
1019 		       "though there is no buffered frames for it\n",
1020 		       rx->dev->name, print_mac(mac, rx->sta->addr));
1021 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1022 	}
1023 
1024 	/* Free PS Poll skb here instead of returning RX_DROP that would
1025 	 * count as an dropped frame. */
1026 	dev_kfree_skb(rx->skb);
1027 
1028 	return RX_QUEUED;
1029 }
1030 
1031 static ieee80211_rx_result
1032 ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx)
1033 {
1034 	u16 fc = rx->fc;
1035 	u8 *data = rx->skb->data;
1036 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) data;
1037 
1038 	if (!WLAN_FC_IS_QOS_DATA(fc))
1039 		return RX_CONTINUE;
1040 
1041 	/* remove the qos control field, update frame type and meta-data */
1042 	memmove(data + 2, data, ieee80211_get_hdrlen(fc) - 2);
1043 	hdr = (struct ieee80211_hdr *) skb_pull(rx->skb, 2);
1044 	/* change frame type to non QOS */
1045 	rx->fc = fc &= ~IEEE80211_STYPE_QOS_DATA;
1046 	hdr->frame_control = cpu_to_le16(fc);
1047 
1048 	return RX_CONTINUE;
1049 }
1050 
1051 static int
1052 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1053 {
1054 	if (unlikely(!rx->sta || !(rx->sta->flags & WLAN_STA_AUTHORIZED))) {
1055 #ifdef CONFIG_MAC80211_DEBUG
1056 		if (net_ratelimit())
1057 			printk(KERN_DEBUG "%s: dropped frame "
1058 			       "(unauthorized port)\n", rx->dev->name);
1059 #endif /* CONFIG_MAC80211_DEBUG */
1060 		return -EACCES;
1061 	}
1062 
1063 	return 0;
1064 }
1065 
1066 static int
1067 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx)
1068 {
1069 	/*
1070 	 * Pass through unencrypted frames if the hardware has
1071 	 * decrypted them already.
1072 	 */
1073 	if (rx->status->flag & RX_FLAG_DECRYPTED)
1074 		return 0;
1075 
1076 	/* Drop unencrypted frames if key is set. */
1077 	if (unlikely(!(rx->fc & IEEE80211_FCTL_PROTECTED) &&
1078 		     (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
1079 		     (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_NULLFUNC &&
1080 		     (rx->key || rx->sdata->drop_unencrypted)))
1081 		return -EACCES;
1082 
1083 	return 0;
1084 }
1085 
1086 static int
1087 ieee80211_data_to_8023(struct ieee80211_rx_data *rx)
1088 {
1089 	struct net_device *dev = rx->dev;
1090 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
1091 	u16 fc, hdrlen, ethertype;
1092 	u8 *payload;
1093 	u8 dst[ETH_ALEN];
1094 	u8 src[ETH_ALEN];
1095 	struct sk_buff *skb = rx->skb;
1096 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1097 	DECLARE_MAC_BUF(mac);
1098 	DECLARE_MAC_BUF(mac2);
1099 	DECLARE_MAC_BUF(mac3);
1100 	DECLARE_MAC_BUF(mac4);
1101 
1102 	fc = rx->fc;
1103 
1104 	if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
1105 		return -1;
1106 
1107 	hdrlen = ieee80211_get_hdrlen(fc);
1108 
1109 	if (ieee80211_vif_is_mesh(&sdata->vif)) {
1110 		int meshhdrlen = ieee80211_get_mesh_hdrlen(
1111 				(struct ieee80211s_hdr *) (skb->data + hdrlen));
1112 		/* Copy on cb:
1113 		 *  - mesh header: to be used for mesh forwarding
1114 		 * decision. It will also be used as mesh header template at
1115 		 * tx.c:ieee80211_subif_start_xmit() if interface
1116 		 * type is mesh and skb->pkt_type == PACKET_OTHERHOST
1117 		 *  - ta: to be used if a RERR needs to be sent.
1118 		 */
1119 		memcpy(skb->cb, skb->data + hdrlen, meshhdrlen);
1120 		memcpy(MESH_PREQ(skb), hdr->addr2, ETH_ALEN);
1121 		hdrlen += meshhdrlen;
1122 	}
1123 
1124 	/* convert IEEE 802.11 header + possible LLC headers into Ethernet
1125 	 * header
1126 	 * IEEE 802.11 address fields:
1127 	 * ToDS FromDS Addr1 Addr2 Addr3 Addr4
1128 	 *   0     0   DA    SA    BSSID n/a
1129 	 *   0     1   DA    BSSID SA    n/a
1130 	 *   1     0   BSSID SA    DA    n/a
1131 	 *   1     1   RA    TA    DA    SA
1132 	 */
1133 
1134 	switch (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
1135 	case IEEE80211_FCTL_TODS:
1136 		/* BSSID SA DA */
1137 		memcpy(dst, hdr->addr3, ETH_ALEN);
1138 		memcpy(src, hdr->addr2, ETH_ALEN);
1139 
1140 		if (unlikely(sdata->vif.type != IEEE80211_IF_TYPE_AP &&
1141 			     sdata->vif.type != IEEE80211_IF_TYPE_VLAN)) {
1142 			if (net_ratelimit())
1143 				printk(KERN_DEBUG "%s: dropped ToDS frame "
1144 				       "(BSSID=%s SA=%s DA=%s)\n",
1145 				       dev->name,
1146 				       print_mac(mac, hdr->addr1),
1147 				       print_mac(mac2, hdr->addr2),
1148 				       print_mac(mac3, hdr->addr3));
1149 			return -1;
1150 		}
1151 		break;
1152 	case (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
1153 		/* RA TA DA SA */
1154 		memcpy(dst, hdr->addr3, ETH_ALEN);
1155 		memcpy(src, hdr->addr4, ETH_ALEN);
1156 
1157 		 if (unlikely(sdata->vif.type != IEEE80211_IF_TYPE_WDS &&
1158 			     sdata->vif.type != IEEE80211_IF_TYPE_MESH_POINT)) {
1159 			 if (net_ratelimit())
1160 				 printk(KERN_DEBUG "%s: dropped FromDS&ToDS "
1161 				       "frame (RA=%s TA=%s DA=%s SA=%s)\n",
1162 				       rx->dev->name,
1163 				       print_mac(mac, hdr->addr1),
1164 				       print_mac(mac2, hdr->addr2),
1165 				       print_mac(mac3, hdr->addr3),
1166 				       print_mac(mac4, hdr->addr4));
1167 			return -1;
1168 		}
1169 		break;
1170 	case IEEE80211_FCTL_FROMDS:
1171 		/* DA BSSID SA */
1172 		memcpy(dst, hdr->addr1, ETH_ALEN);
1173 		memcpy(src, hdr->addr3, ETH_ALEN);
1174 
1175 		if (sdata->vif.type != IEEE80211_IF_TYPE_STA ||
1176 		    (is_multicast_ether_addr(dst) &&
1177 		     !compare_ether_addr(src, dev->dev_addr)))
1178 			return -1;
1179 		break;
1180 	case 0:
1181 		/* DA SA BSSID */
1182 		memcpy(dst, hdr->addr1, ETH_ALEN);
1183 		memcpy(src, hdr->addr2, ETH_ALEN);
1184 
1185 		if (sdata->vif.type != IEEE80211_IF_TYPE_IBSS) {
1186 			if (net_ratelimit()) {
1187 				printk(KERN_DEBUG "%s: dropped IBSS frame "
1188 				       "(DA=%s SA=%s BSSID=%s)\n",
1189 				       dev->name,
1190 				       print_mac(mac, hdr->addr1),
1191 				       print_mac(mac2, hdr->addr2),
1192 				       print_mac(mac3, hdr->addr3));
1193 			}
1194 			return -1;
1195 		}
1196 		break;
1197 	}
1198 
1199 	if (unlikely(skb->len - hdrlen < 8)) {
1200 		if (net_ratelimit()) {
1201 			printk(KERN_DEBUG "%s: RX too short data frame "
1202 			       "payload\n", dev->name);
1203 		}
1204 		return -1;
1205 	}
1206 
1207 	payload = skb->data + hdrlen;
1208 	ethertype = (payload[6] << 8) | payload[7];
1209 
1210 	if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1211 		    ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1212 		   compare_ether_addr(payload, bridge_tunnel_header) == 0)) {
1213 		/* remove RFC1042 or Bridge-Tunnel encapsulation and
1214 		 * replace EtherType */
1215 		skb_pull(skb, hdrlen + 6);
1216 		memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
1217 		memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
1218 	} else {
1219 		struct ethhdr *ehdr;
1220 		__be16 len;
1221 
1222 		skb_pull(skb, hdrlen);
1223 		len = htons(skb->len);
1224 		ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
1225 		memcpy(ehdr->h_dest, dst, ETH_ALEN);
1226 		memcpy(ehdr->h_source, src, ETH_ALEN);
1227 		ehdr->h_proto = len;
1228 	}
1229 	return 0;
1230 }
1231 
1232 /*
1233  * requires that rx->skb is a frame with ethernet header
1234  */
1235 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx)
1236 {
1237 	static const u8 pae_group_addr[ETH_ALEN]
1238 		= { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1239 	struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1240 
1241 	/*
1242 	 * Allow EAPOL frames to us/the PAE group address regardless
1243 	 * of whether the frame was encrypted or not.
1244 	 */
1245 	if (ehdr->h_proto == htons(ETH_P_PAE) &&
1246 	    (compare_ether_addr(ehdr->h_dest, rx->dev->dev_addr) == 0 ||
1247 	     compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
1248 		return true;
1249 
1250 	if (ieee80211_802_1x_port_control(rx) ||
1251 	    ieee80211_drop_unencrypted(rx))
1252 		return false;
1253 
1254 	return true;
1255 }
1256 
1257 /*
1258  * requires that rx->skb is a frame with ethernet header
1259  */
1260 static void
1261 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1262 {
1263 	struct net_device *dev = rx->dev;
1264 	struct ieee80211_local *local = rx->local;
1265 	struct sk_buff *skb, *xmit_skb;
1266 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1267 	struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1268 	struct sta_info *dsta;
1269 
1270 	skb = rx->skb;
1271 	xmit_skb = NULL;
1272 
1273 	if (local->bridge_packets && (sdata->vif.type == IEEE80211_IF_TYPE_AP ||
1274 				      sdata->vif.type == IEEE80211_IF_TYPE_VLAN) &&
1275 	    (rx->flags & IEEE80211_RX_RA_MATCH)) {
1276 		if (is_multicast_ether_addr(ehdr->h_dest)) {
1277 			/*
1278 			 * send multicast frames both to higher layers in
1279 			 * local net stack and back to the wireless medium
1280 			 */
1281 			xmit_skb = skb_copy(skb, GFP_ATOMIC);
1282 			if (!xmit_skb && net_ratelimit())
1283 				printk(KERN_DEBUG "%s: failed to clone "
1284 				       "multicast frame\n", dev->name);
1285 		} else {
1286 			dsta = sta_info_get(local, skb->data);
1287 			if (dsta && dsta->sdata->dev == dev) {
1288 				/*
1289 				 * The destination station is associated to
1290 				 * this AP (in this VLAN), so send the frame
1291 				 * directly to it and do not pass it to local
1292 				 * net stack.
1293 				 */
1294 				xmit_skb = skb;
1295 				skb = NULL;
1296 			}
1297 		}
1298 	}
1299 
1300 	/* Mesh forwarding */
1301 	if (ieee80211_vif_is_mesh(&sdata->vif)) {
1302 		u8 *mesh_ttl = &((struct ieee80211s_hdr *)skb->cb)->ttl;
1303 		(*mesh_ttl)--;
1304 
1305 		if (is_multicast_ether_addr(skb->data)) {
1306 			if (*mesh_ttl > 0) {
1307 				xmit_skb = skb_copy(skb, GFP_ATOMIC);
1308 				if (xmit_skb)
1309 					xmit_skb->pkt_type = PACKET_OTHERHOST;
1310 				else if (net_ratelimit())
1311 					printk(KERN_DEBUG "%s: failed to clone "
1312 					       "multicast frame\n", dev->name);
1313 			} else
1314 				IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.sta,
1315 							     dropped_frames_ttl);
1316 		} else if (skb->pkt_type != PACKET_OTHERHOST &&
1317 			compare_ether_addr(dev->dev_addr, skb->data) != 0) {
1318 			if (*mesh_ttl == 0) {
1319 				IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.sta,
1320 							     dropped_frames_ttl);
1321 				dev_kfree_skb(skb);
1322 				skb = NULL;
1323 			} else {
1324 				xmit_skb = skb;
1325 				xmit_skb->pkt_type = PACKET_OTHERHOST;
1326 				if (!(dev->flags & IFF_PROMISC))
1327 					skb  = NULL;
1328 			}
1329 		}
1330 	}
1331 
1332 	if (skb) {
1333 		/* deliver to local stack */
1334 		skb->protocol = eth_type_trans(skb, dev);
1335 		memset(skb->cb, 0, sizeof(skb->cb));
1336 		netif_rx(skb);
1337 	}
1338 
1339 	if (xmit_skb) {
1340 		/* send to wireless media */
1341 		xmit_skb->protocol = htons(ETH_P_802_3);
1342 		skb_reset_network_header(xmit_skb);
1343 		skb_reset_mac_header(xmit_skb);
1344 		dev_queue_xmit(xmit_skb);
1345 	}
1346 }
1347 
1348 static ieee80211_rx_result
1349 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1350 {
1351 	struct net_device *dev = rx->dev;
1352 	struct ieee80211_local *local = rx->local;
1353 	u16 fc, ethertype;
1354 	u8 *payload;
1355 	struct sk_buff *skb = rx->skb, *frame = NULL;
1356 	const struct ethhdr *eth;
1357 	int remaining, err;
1358 	u8 dst[ETH_ALEN];
1359 	u8 src[ETH_ALEN];
1360 	DECLARE_MAC_BUF(mac);
1361 
1362 	fc = rx->fc;
1363 	if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA))
1364 		return RX_CONTINUE;
1365 
1366 	if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
1367 		return RX_DROP_MONITOR;
1368 
1369 	if (!(rx->flags & IEEE80211_RX_AMSDU))
1370 		return RX_CONTINUE;
1371 
1372 	err = ieee80211_data_to_8023(rx);
1373 	if (unlikely(err))
1374 		return RX_DROP_UNUSABLE;
1375 
1376 	skb->dev = dev;
1377 
1378 	dev->stats.rx_packets++;
1379 	dev->stats.rx_bytes += skb->len;
1380 
1381 	/* skip the wrapping header */
1382 	eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
1383 	if (!eth)
1384 		return RX_DROP_UNUSABLE;
1385 
1386 	while (skb != frame) {
1387 		u8 padding;
1388 		__be16 len = eth->h_proto;
1389 		unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);
1390 
1391 		remaining = skb->len;
1392 		memcpy(dst, eth->h_dest, ETH_ALEN);
1393 		memcpy(src, eth->h_source, ETH_ALEN);
1394 
1395 		padding = ((4 - subframe_len) & 0x3);
1396 		/* the last MSDU has no padding */
1397 		if (subframe_len > remaining) {
1398 			printk(KERN_DEBUG "%s: wrong buffer size\n", dev->name);
1399 			return RX_DROP_UNUSABLE;
1400 		}
1401 
1402 		skb_pull(skb, sizeof(struct ethhdr));
1403 		/* if last subframe reuse skb */
1404 		if (remaining <= subframe_len + padding)
1405 			frame = skb;
1406 		else {
1407 			frame = dev_alloc_skb(local->hw.extra_tx_headroom +
1408 					      subframe_len);
1409 
1410 			if (frame == NULL)
1411 				return RX_DROP_UNUSABLE;
1412 
1413 			skb_reserve(frame, local->hw.extra_tx_headroom +
1414 				    sizeof(struct ethhdr));
1415 			memcpy(skb_put(frame, ntohs(len)), skb->data,
1416 				ntohs(len));
1417 
1418 			eth = (struct ethhdr *) skb_pull(skb, ntohs(len) +
1419 							padding);
1420 			if (!eth) {
1421 				printk(KERN_DEBUG "%s: wrong buffer size\n",
1422 				       dev->name);
1423 				dev_kfree_skb(frame);
1424 				return RX_DROP_UNUSABLE;
1425 			}
1426 		}
1427 
1428 		skb_reset_network_header(frame);
1429 		frame->dev = dev;
1430 		frame->priority = skb->priority;
1431 		rx->skb = frame;
1432 
1433 		payload = frame->data;
1434 		ethertype = (payload[6] << 8) | payload[7];
1435 
1436 		if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1437 			    ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1438 			   compare_ether_addr(payload,
1439 					      bridge_tunnel_header) == 0)) {
1440 			/* remove RFC1042 or Bridge-Tunnel
1441 			 * encapsulation and replace EtherType */
1442 			skb_pull(frame, 6);
1443 			memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1444 			memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1445 		} else {
1446 			memcpy(skb_push(frame, sizeof(__be16)),
1447 			       &len, sizeof(__be16));
1448 			memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1449 			memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1450 		}
1451 
1452 		if (!ieee80211_frame_allowed(rx)) {
1453 			if (skb == frame) /* last frame */
1454 				return RX_DROP_UNUSABLE;
1455 			dev_kfree_skb(frame);
1456 			continue;
1457 		}
1458 
1459 		ieee80211_deliver_skb(rx);
1460 	}
1461 
1462 	return RX_QUEUED;
1463 }
1464 
1465 static ieee80211_rx_result
1466 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
1467 {
1468 	struct net_device *dev = rx->dev;
1469 	u16 fc;
1470 	int err;
1471 
1472 	fc = rx->fc;
1473 	if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA))
1474 		return RX_CONTINUE;
1475 
1476 	if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
1477 		return RX_DROP_MONITOR;
1478 
1479 	err = ieee80211_data_to_8023(rx);
1480 	if (unlikely(err))
1481 		return RX_DROP_UNUSABLE;
1482 
1483 	if (!ieee80211_frame_allowed(rx))
1484 		return RX_DROP_MONITOR;
1485 
1486 	rx->skb->dev = dev;
1487 
1488 	dev->stats.rx_packets++;
1489 	dev->stats.rx_bytes += rx->skb->len;
1490 
1491 	ieee80211_deliver_skb(rx);
1492 
1493 	return RX_QUEUED;
1494 }
1495 
1496 static ieee80211_rx_result
1497 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx)
1498 {
1499 	struct ieee80211_local *local = rx->local;
1500 	struct ieee80211_hw *hw = &local->hw;
1501 	struct sk_buff *skb = rx->skb;
1502 	struct ieee80211_bar *bar = (struct ieee80211_bar *) skb->data;
1503 	struct tid_ampdu_rx *tid_agg_rx;
1504 	u16 start_seq_num;
1505 	u16 tid;
1506 
1507 	if (likely((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_CTL))
1508 		return RX_CONTINUE;
1509 
1510 	if ((rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_BACK_REQ) {
1511 		if (!rx->sta)
1512 			return RX_CONTINUE;
1513 		tid = le16_to_cpu(bar->control) >> 12;
1514 		if (rx->sta->ampdu_mlme.tid_state_rx[tid]
1515 					!= HT_AGG_STATE_OPERATIONAL)
1516 			return RX_CONTINUE;
1517 		tid_agg_rx = rx->sta->ampdu_mlme.tid_rx[tid];
1518 
1519 		start_seq_num = le16_to_cpu(bar->start_seq_num) >> 4;
1520 
1521 		/* reset session timer */
1522 		if (tid_agg_rx->timeout) {
1523 			unsigned long expires =
1524 				jiffies + (tid_agg_rx->timeout / 1000) * HZ;
1525 			mod_timer(&tid_agg_rx->session_timer, expires);
1526 		}
1527 
1528 		/* manage reordering buffer according to requested */
1529 		/* sequence number */
1530 		rcu_read_lock();
1531 		ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, NULL,
1532 						 start_seq_num, 1);
1533 		rcu_read_unlock();
1534 		return RX_DROP_UNUSABLE;
1535 	}
1536 
1537 	return RX_CONTINUE;
1538 }
1539 
1540 static ieee80211_rx_result
1541 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
1542 {
1543 	struct ieee80211_sub_if_data *sdata;
1544 
1545 	if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1546 		return RX_DROP_MONITOR;
1547 
1548 	sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1549 	if ((sdata->vif.type == IEEE80211_IF_TYPE_STA ||
1550 	     sdata->vif.type == IEEE80211_IF_TYPE_IBSS ||
1551 	     sdata->vif.type == IEEE80211_IF_TYPE_MESH_POINT) &&
1552 	    !(sdata->flags & IEEE80211_SDATA_USERSPACE_MLME))
1553 		ieee80211_sta_rx_mgmt(rx->dev, rx->skb, rx->status);
1554 	else
1555 		return RX_DROP_MONITOR;
1556 
1557 	return RX_QUEUED;
1558 }
1559 
1560 static void ieee80211_rx_michael_mic_report(struct net_device *dev,
1561 					    struct ieee80211_hdr *hdr,
1562 					    struct ieee80211_rx_data *rx)
1563 {
1564 	int keyidx, hdrlen;
1565 	DECLARE_MAC_BUF(mac);
1566 	DECLARE_MAC_BUF(mac2);
1567 
1568 	hdrlen = ieee80211_get_hdrlen_from_skb(rx->skb);
1569 	if (rx->skb->len >= hdrlen + 4)
1570 		keyidx = rx->skb->data[hdrlen + 3] >> 6;
1571 	else
1572 		keyidx = -1;
1573 
1574 	if (net_ratelimit())
1575 		printk(KERN_DEBUG "%s: TKIP hwaccel reported Michael MIC "
1576 		       "failure from %s to %s keyidx=%d\n",
1577 		       dev->name, print_mac(mac, hdr->addr2),
1578 		       print_mac(mac2, hdr->addr1), keyidx);
1579 
1580 	if (!rx->sta) {
1581 		/*
1582 		 * Some hardware seem to generate incorrect Michael MIC
1583 		 * reports; ignore them to avoid triggering countermeasures.
1584 		 */
1585 		if (net_ratelimit())
1586 			printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1587 			       "error for unknown address %s\n",
1588 			       dev->name, print_mac(mac, hdr->addr2));
1589 		goto ignore;
1590 	}
1591 
1592 	if (!(rx->fc & IEEE80211_FCTL_PROTECTED)) {
1593 		if (net_ratelimit())
1594 			printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1595 			       "error for a frame with no PROTECTED flag (src "
1596 			       "%s)\n", dev->name, print_mac(mac, hdr->addr2));
1597 		goto ignore;
1598 	}
1599 
1600 	if (rx->sdata->vif.type == IEEE80211_IF_TYPE_AP && keyidx) {
1601 		/*
1602 		 * APs with pairwise keys should never receive Michael MIC
1603 		 * errors for non-zero keyidx because these are reserved for
1604 		 * group keys and only the AP is sending real multicast
1605 		 * frames in the BSS.
1606 		 */
1607 		if (net_ratelimit())
1608 			printk(KERN_DEBUG "%s: ignored Michael MIC error for "
1609 			       "a frame with non-zero keyidx (%d)"
1610 			       " (src %s)\n", dev->name, keyidx,
1611 			       print_mac(mac, hdr->addr2));
1612 		goto ignore;
1613 	}
1614 
1615 	if ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA &&
1616 	    ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT ||
1617 	     (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_AUTH)) {
1618 		if (net_ratelimit())
1619 			printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1620 			       "error for a frame that cannot be encrypted "
1621 			       "(fc=0x%04x) (src %s)\n",
1622 			       dev->name, rx->fc, print_mac(mac, hdr->addr2));
1623 		goto ignore;
1624 	}
1625 
1626 	mac80211_ev_michael_mic_failure(rx->dev, keyidx, hdr);
1627  ignore:
1628 	dev_kfree_skb(rx->skb);
1629 	rx->skb = NULL;
1630 }
1631 
1632 /* TODO: use IEEE80211_RX_FRAGMENTED */
1633 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx)
1634 {
1635 	struct ieee80211_sub_if_data *sdata;
1636 	struct ieee80211_local *local = rx->local;
1637 	struct ieee80211_rtap_hdr {
1638 		struct ieee80211_radiotap_header hdr;
1639 		u8 flags;
1640 		u8 rate;
1641 		__le16 chan_freq;
1642 		__le16 chan_flags;
1643 	} __attribute__ ((packed)) *rthdr;
1644 	struct sk_buff *skb = rx->skb, *skb2;
1645 	struct net_device *prev_dev = NULL;
1646 	struct ieee80211_rx_status *status = rx->status;
1647 
1648 	if (rx->flags & IEEE80211_RX_CMNTR_REPORTED)
1649 		goto out_free_skb;
1650 
1651 	if (skb_headroom(skb) < sizeof(*rthdr) &&
1652 	    pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC))
1653 		goto out_free_skb;
1654 
1655 	rthdr = (void *)skb_push(skb, sizeof(*rthdr));
1656 	memset(rthdr, 0, sizeof(*rthdr));
1657 	rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
1658 	rthdr->hdr.it_present =
1659 		cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
1660 			    (1 << IEEE80211_RADIOTAP_RATE) |
1661 			    (1 << IEEE80211_RADIOTAP_CHANNEL));
1662 
1663 	rthdr->rate = rx->rate->bitrate / 5;
1664 	rthdr->chan_freq = cpu_to_le16(status->freq);
1665 
1666 	if (status->band == IEEE80211_BAND_5GHZ)
1667 		rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM |
1668 						IEEE80211_CHAN_5GHZ);
1669 	else
1670 		rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN |
1671 						IEEE80211_CHAN_2GHZ);
1672 
1673 	skb_set_mac_header(skb, 0);
1674 	skb->ip_summed = CHECKSUM_UNNECESSARY;
1675 	skb->pkt_type = PACKET_OTHERHOST;
1676 	skb->protocol = htons(ETH_P_802_2);
1677 
1678 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
1679 		if (!netif_running(sdata->dev))
1680 			continue;
1681 
1682 		if (sdata->vif.type != IEEE80211_IF_TYPE_MNTR ||
1683 		    !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
1684 			continue;
1685 
1686 		if (prev_dev) {
1687 			skb2 = skb_clone(skb, GFP_ATOMIC);
1688 			if (skb2) {
1689 				skb2->dev = prev_dev;
1690 				netif_rx(skb2);
1691 			}
1692 		}
1693 
1694 		prev_dev = sdata->dev;
1695 		sdata->dev->stats.rx_packets++;
1696 		sdata->dev->stats.rx_bytes += skb->len;
1697 	}
1698 
1699 	if (prev_dev) {
1700 		skb->dev = prev_dev;
1701 		netif_rx(skb);
1702 		skb = NULL;
1703 	} else
1704 		goto out_free_skb;
1705 
1706 	rx->flags |= IEEE80211_RX_CMNTR_REPORTED;
1707 	return;
1708 
1709  out_free_skb:
1710 	dev_kfree_skb(skb);
1711 }
1712 
1713 typedef ieee80211_rx_result (*ieee80211_rx_handler)(struct ieee80211_rx_data *);
1714 static ieee80211_rx_handler ieee80211_rx_handlers[] =
1715 {
1716 	ieee80211_rx_h_if_stats,
1717 	ieee80211_rx_h_passive_scan,
1718 	ieee80211_rx_h_check,
1719 	ieee80211_rx_h_decrypt,
1720 	ieee80211_rx_h_sta_process,
1721 	ieee80211_rx_h_defragment,
1722 	ieee80211_rx_h_ps_poll,
1723 	ieee80211_rx_h_michael_mic_verify,
1724 	/* this must be after decryption - so header is counted in MPDU mic
1725 	 * must be before pae and data, so QOS_DATA format frames
1726 	 * are not passed to user space by these functions
1727 	 */
1728 	ieee80211_rx_h_remove_qos_control,
1729 	ieee80211_rx_h_amsdu,
1730 	ieee80211_rx_h_data,
1731 	ieee80211_rx_h_ctrl,
1732 	ieee80211_rx_h_mgmt,
1733 	NULL
1734 };
1735 
1736 static void ieee80211_invoke_rx_handlers(struct ieee80211_sub_if_data *sdata,
1737 					 struct ieee80211_rx_data *rx,
1738 					 struct sk_buff *skb)
1739 {
1740 	ieee80211_rx_handler *handler;
1741 	ieee80211_rx_result res = RX_DROP_MONITOR;
1742 
1743 	rx->skb = skb;
1744 	rx->sdata = sdata;
1745 	rx->dev = sdata->dev;
1746 
1747 	for (handler = ieee80211_rx_handlers; *handler != NULL; handler++) {
1748 		res = (*handler)(rx);
1749 
1750 		switch (res) {
1751 		case RX_CONTINUE:
1752 			continue;
1753 		case RX_DROP_UNUSABLE:
1754 		case RX_DROP_MONITOR:
1755 			I802_DEBUG_INC(sdata->local->rx_handlers_drop);
1756 			if (rx->sta)
1757 				rx->sta->rx_dropped++;
1758 			break;
1759 		case RX_QUEUED:
1760 			I802_DEBUG_INC(sdata->local->rx_handlers_queued);
1761 			break;
1762 		}
1763 		break;
1764 	}
1765 
1766 	switch (res) {
1767 	case RX_CONTINUE:
1768 	case RX_DROP_MONITOR:
1769 		ieee80211_rx_cooked_monitor(rx);
1770 		break;
1771 	case RX_DROP_UNUSABLE:
1772 		dev_kfree_skb(rx->skb);
1773 		break;
1774 	}
1775 }
1776 
1777 /* main receive path */
1778 
1779 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata,
1780 				u8 *bssid, struct ieee80211_rx_data *rx,
1781 				struct ieee80211_hdr *hdr)
1782 {
1783 	int multicast = is_multicast_ether_addr(hdr->addr1);
1784 
1785 	switch (sdata->vif.type) {
1786 	case IEEE80211_IF_TYPE_STA:
1787 		if (!bssid)
1788 			return 0;
1789 		if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1790 			if (!(rx->flags & IEEE80211_RX_IN_SCAN))
1791 				return 0;
1792 			rx->flags &= ~IEEE80211_RX_RA_MATCH;
1793 		} else if (!multicast &&
1794 			   compare_ether_addr(sdata->dev->dev_addr,
1795 					      hdr->addr1) != 0) {
1796 			if (!(sdata->dev->flags & IFF_PROMISC))
1797 				return 0;
1798 			rx->flags &= ~IEEE80211_RX_RA_MATCH;
1799 		}
1800 		break;
1801 	case IEEE80211_IF_TYPE_IBSS:
1802 		if (!bssid)
1803 			return 0;
1804 		if ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_MGMT &&
1805 		    (rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_BEACON)
1806 			return 1;
1807 		else if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1808 			if (!(rx->flags & IEEE80211_RX_IN_SCAN))
1809 				return 0;
1810 			rx->flags &= ~IEEE80211_RX_RA_MATCH;
1811 		} else if (!multicast &&
1812 			   compare_ether_addr(sdata->dev->dev_addr,
1813 					      hdr->addr1) != 0) {
1814 			if (!(sdata->dev->flags & IFF_PROMISC))
1815 				return 0;
1816 			rx->flags &= ~IEEE80211_RX_RA_MATCH;
1817 		} else if (!rx->sta)
1818 			rx->sta = ieee80211_ibss_add_sta(sdata->dev, rx->skb,
1819 							 bssid, hdr->addr2);
1820 		break;
1821 	case IEEE80211_IF_TYPE_MESH_POINT:
1822 		if (!multicast &&
1823 		    compare_ether_addr(sdata->dev->dev_addr,
1824 				       hdr->addr1) != 0) {
1825 			if (!(sdata->dev->flags & IFF_PROMISC))
1826 				return 0;
1827 
1828 			rx->flags &= ~IEEE80211_RX_RA_MATCH;
1829 		}
1830 		break;
1831 	case IEEE80211_IF_TYPE_VLAN:
1832 	case IEEE80211_IF_TYPE_AP:
1833 		if (!bssid) {
1834 			if (compare_ether_addr(sdata->dev->dev_addr,
1835 					       hdr->addr1))
1836 				return 0;
1837 		} else if (!ieee80211_bssid_match(bssid,
1838 					sdata->dev->dev_addr)) {
1839 			if (!(rx->flags & IEEE80211_RX_IN_SCAN))
1840 				return 0;
1841 			rx->flags &= ~IEEE80211_RX_RA_MATCH;
1842 		}
1843 		if (sdata->dev == sdata->local->mdev &&
1844 		    !(rx->flags & IEEE80211_RX_IN_SCAN))
1845 			/* do not receive anything via
1846 			 * master device when not scanning */
1847 			return 0;
1848 		break;
1849 	case IEEE80211_IF_TYPE_WDS:
1850 		if (bssid ||
1851 		    (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)
1852 			return 0;
1853 		if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
1854 			return 0;
1855 		break;
1856 	case IEEE80211_IF_TYPE_MNTR:
1857 		/* take everything */
1858 		break;
1859 	case IEEE80211_IF_TYPE_INVALID:
1860 		/* should never get here */
1861 		WARN_ON(1);
1862 		break;
1863 	}
1864 
1865 	return 1;
1866 }
1867 
1868 /*
1869  * This is the actual Rx frames handler. as it blongs to Rx path it must
1870  * be called with rcu_read_lock protection.
1871  */
1872 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
1873 					 struct sk_buff *skb,
1874 					 struct ieee80211_rx_status *status,
1875 					 u32 load,
1876 					 struct ieee80211_rate *rate)
1877 {
1878 	struct ieee80211_local *local = hw_to_local(hw);
1879 	struct ieee80211_sub_if_data *sdata;
1880 	struct ieee80211_hdr *hdr;
1881 	struct ieee80211_rx_data rx;
1882 	u16 type;
1883 	int prepares;
1884 	struct ieee80211_sub_if_data *prev = NULL;
1885 	struct sk_buff *skb_new;
1886 	u8 *bssid;
1887 
1888 	hdr = (struct ieee80211_hdr *) skb->data;
1889 	memset(&rx, 0, sizeof(rx));
1890 	rx.skb = skb;
1891 	rx.local = local;
1892 
1893 	rx.status = status;
1894 	rx.load = load;
1895 	rx.rate = rate;
1896 	rx.fc = le16_to_cpu(hdr->frame_control);
1897 	type = rx.fc & IEEE80211_FCTL_FTYPE;
1898 
1899 	if (type == IEEE80211_FTYPE_DATA || type == IEEE80211_FTYPE_MGMT)
1900 		local->dot11ReceivedFragmentCount++;
1901 
1902 	rx.sta = sta_info_get(local, hdr->addr2);
1903 	if (rx.sta) {
1904 		rx.sdata = rx.sta->sdata;
1905 		rx.dev = rx.sta->sdata->dev;
1906 	}
1907 
1908 	if ((status->flag & RX_FLAG_MMIC_ERROR)) {
1909 		ieee80211_rx_michael_mic_report(local->mdev, hdr, &rx);
1910 		return;
1911 	}
1912 
1913 	if (unlikely(local->sta_sw_scanning || local->sta_hw_scanning))
1914 		rx.flags |= IEEE80211_RX_IN_SCAN;
1915 
1916 	ieee80211_parse_qos(&rx);
1917 	ieee80211_verify_ip_alignment(&rx);
1918 
1919 	skb = rx.skb;
1920 
1921 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
1922 		if (!netif_running(sdata->dev))
1923 			continue;
1924 
1925 		if (sdata->vif.type == IEEE80211_IF_TYPE_MNTR)
1926 			continue;
1927 
1928 		bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
1929 		rx.flags |= IEEE80211_RX_RA_MATCH;
1930 		prepares = prepare_for_handlers(sdata, bssid, &rx, hdr);
1931 
1932 		if (!prepares)
1933 			continue;
1934 
1935 		/*
1936 		 * frame is destined for this interface, but if it's not
1937 		 * also for the previous one we handle that after the
1938 		 * loop to avoid copying the SKB once too much
1939 		 */
1940 
1941 		if (!prev) {
1942 			prev = sdata;
1943 			continue;
1944 		}
1945 
1946 		/*
1947 		 * frame was destined for the previous interface
1948 		 * so invoke RX handlers for it
1949 		 */
1950 
1951 		skb_new = skb_copy(skb, GFP_ATOMIC);
1952 		if (!skb_new) {
1953 			if (net_ratelimit())
1954 				printk(KERN_DEBUG "%s: failed to copy "
1955 				       "multicast frame for %s\n",
1956 				       wiphy_name(local->hw.wiphy),
1957 				       prev->dev->name);
1958 			continue;
1959 		}
1960 		rx.fc = le16_to_cpu(hdr->frame_control);
1961 		ieee80211_invoke_rx_handlers(prev, &rx, skb_new);
1962 		prev = sdata;
1963 	}
1964 	if (prev) {
1965 		rx.fc = le16_to_cpu(hdr->frame_control);
1966 		ieee80211_invoke_rx_handlers(prev, &rx, skb);
1967 	} else
1968 		dev_kfree_skb(skb);
1969 }
1970 
1971 #define SEQ_MODULO 0x1000
1972 #define SEQ_MASK   0xfff
1973 
1974 static inline int seq_less(u16 sq1, u16 sq2)
1975 {
1976 	return (((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1));
1977 }
1978 
1979 static inline u16 seq_inc(u16 sq)
1980 {
1981 	return ((sq + 1) & SEQ_MASK);
1982 }
1983 
1984 static inline u16 seq_sub(u16 sq1, u16 sq2)
1985 {
1986 	return ((sq1 - sq2) & SEQ_MASK);
1987 }
1988 
1989 
1990 /*
1991  * As it function blongs to Rx path it must be called with
1992  * the proper rcu_read_lock protection for its flow.
1993  */
1994 u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
1995 				struct tid_ampdu_rx *tid_agg_rx,
1996 				struct sk_buff *skb, u16 mpdu_seq_num,
1997 				int bar_req)
1998 {
1999 	struct ieee80211_local *local = hw_to_local(hw);
2000 	struct ieee80211_rx_status status;
2001 	u16 head_seq_num, buf_size;
2002 	int index;
2003 	u32 pkt_load;
2004 	struct ieee80211_supported_band *sband;
2005 	struct ieee80211_rate *rate;
2006 
2007 	buf_size = tid_agg_rx->buf_size;
2008 	head_seq_num = tid_agg_rx->head_seq_num;
2009 
2010 	/* frame with out of date sequence number */
2011 	if (seq_less(mpdu_seq_num, head_seq_num)) {
2012 		dev_kfree_skb(skb);
2013 		return 1;
2014 	}
2015 
2016 	/* if frame sequence number exceeds our buffering window size or
2017 	 * block Ack Request arrived - release stored frames */
2018 	if ((!seq_less(mpdu_seq_num, head_seq_num + buf_size)) || (bar_req)) {
2019 		/* new head to the ordering buffer */
2020 		if (bar_req)
2021 			head_seq_num = mpdu_seq_num;
2022 		else
2023 			head_seq_num =
2024 				seq_inc(seq_sub(mpdu_seq_num, buf_size));
2025 		/* release stored frames up to new head to stack */
2026 		while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
2027 			index = seq_sub(tid_agg_rx->head_seq_num,
2028 				tid_agg_rx->ssn)
2029 				% tid_agg_rx->buf_size;
2030 
2031 			if (tid_agg_rx->reorder_buf[index]) {
2032 				/* release the reordered frames to stack */
2033 				memcpy(&status,
2034 					tid_agg_rx->reorder_buf[index]->cb,
2035 					sizeof(status));
2036 				sband = local->hw.wiphy->bands[status.band];
2037 				rate = &sband->bitrates[status.rate_idx];
2038 				pkt_load = ieee80211_rx_load_stats(local,
2039 						tid_agg_rx->reorder_buf[index],
2040 						&status, rate);
2041 				__ieee80211_rx_handle_packet(hw,
2042 					tid_agg_rx->reorder_buf[index],
2043 					&status, pkt_load, rate);
2044 				tid_agg_rx->stored_mpdu_num--;
2045 				tid_agg_rx->reorder_buf[index] = NULL;
2046 			}
2047 			tid_agg_rx->head_seq_num =
2048 				seq_inc(tid_agg_rx->head_seq_num);
2049 		}
2050 		if (bar_req)
2051 			return 1;
2052 	}
2053 
2054 	/* now the new frame is always in the range of the reordering */
2055 	/* buffer window */
2056 	index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn)
2057 				% tid_agg_rx->buf_size;
2058 	/* check if we already stored this frame */
2059 	if (tid_agg_rx->reorder_buf[index]) {
2060 		dev_kfree_skb(skb);
2061 		return 1;
2062 	}
2063 
2064 	/* if arrived mpdu is in the right order and nothing else stored */
2065 	/* release it immediately */
2066 	if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
2067 			tid_agg_rx->stored_mpdu_num == 0) {
2068 		tid_agg_rx->head_seq_num =
2069 			seq_inc(tid_agg_rx->head_seq_num);
2070 		return 0;
2071 	}
2072 
2073 	/* put the frame in the reordering buffer */
2074 	tid_agg_rx->reorder_buf[index] = skb;
2075 	tid_agg_rx->stored_mpdu_num++;
2076 	/* release the buffer until next missing frame */
2077 	index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn)
2078 						% tid_agg_rx->buf_size;
2079 	while (tid_agg_rx->reorder_buf[index]) {
2080 		/* release the reordered frame back to stack */
2081 		memcpy(&status, tid_agg_rx->reorder_buf[index]->cb,
2082 			sizeof(status));
2083 		sband = local->hw.wiphy->bands[status.band];
2084 		rate = &sband->bitrates[status.rate_idx];
2085 		pkt_load = ieee80211_rx_load_stats(local,
2086 					tid_agg_rx->reorder_buf[index],
2087 					&status, rate);
2088 		__ieee80211_rx_handle_packet(hw, tid_agg_rx->reorder_buf[index],
2089 					     &status, pkt_load, rate);
2090 		tid_agg_rx->stored_mpdu_num--;
2091 		tid_agg_rx->reorder_buf[index] = NULL;
2092 		tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
2093 		index =	seq_sub(tid_agg_rx->head_seq_num,
2094 			tid_agg_rx->ssn) % tid_agg_rx->buf_size;
2095 	}
2096 	return 1;
2097 }
2098 
2099 static u8 ieee80211_rx_reorder_ampdu(struct ieee80211_local *local,
2100 				     struct sk_buff *skb)
2101 {
2102 	struct ieee80211_hw *hw = &local->hw;
2103 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
2104 	struct sta_info *sta;
2105 	struct tid_ampdu_rx *tid_agg_rx;
2106 	u16 fc, sc;
2107 	u16 mpdu_seq_num;
2108 	u8 ret = 0, *qc;
2109 	int tid;
2110 
2111 	sta = sta_info_get(local, hdr->addr2);
2112 	if (!sta)
2113 		return ret;
2114 
2115 	fc = le16_to_cpu(hdr->frame_control);
2116 
2117 	/* filter the QoS data rx stream according to
2118 	 * STA/TID and check if this STA/TID is on aggregation */
2119 	if (!WLAN_FC_IS_QOS_DATA(fc))
2120 		goto end_reorder;
2121 
2122 	qc = skb->data + ieee80211_get_hdrlen(fc) - QOS_CONTROL_LEN;
2123 	tid = qc[0] & QOS_CONTROL_TID_MASK;
2124 
2125 	if (sta->ampdu_mlme.tid_state_rx[tid] != HT_AGG_STATE_OPERATIONAL)
2126 		goto end_reorder;
2127 
2128 	tid_agg_rx = sta->ampdu_mlme.tid_rx[tid];
2129 
2130 	/* null data frames are excluded */
2131 	if (unlikely(fc & IEEE80211_STYPE_NULLFUNC))
2132 		goto end_reorder;
2133 
2134 	/* new un-ordered ampdu frame - process it */
2135 
2136 	/* reset session timer */
2137 	if (tid_agg_rx->timeout) {
2138 		unsigned long expires =
2139 			jiffies + (tid_agg_rx->timeout / 1000) * HZ;
2140 		mod_timer(&tid_agg_rx->session_timer, expires);
2141 	}
2142 
2143 	/* if this mpdu is fragmented - terminate rx aggregation session */
2144 	sc = le16_to_cpu(hdr->seq_ctrl);
2145 	if (sc & IEEE80211_SCTL_FRAG) {
2146 		ieee80211_sta_stop_rx_ba_session(sta->sdata->dev, sta->addr,
2147 			tid, 0, WLAN_REASON_QSTA_REQUIRE_SETUP);
2148 		ret = 1;
2149 		goto end_reorder;
2150 	}
2151 
2152 	/* according to mpdu sequence number deal with reordering buffer */
2153 	mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
2154 	ret = ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb,
2155 						mpdu_seq_num, 0);
2156  end_reorder:
2157 	return ret;
2158 }
2159 
2160 /*
2161  * This is the receive path handler. It is called by a low level driver when an
2162  * 802.11 MPDU is received from the hardware.
2163  */
2164 void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb,
2165 		    struct ieee80211_rx_status *status)
2166 {
2167 	struct ieee80211_local *local = hw_to_local(hw);
2168 	u32 pkt_load;
2169 	struct ieee80211_rate *rate = NULL;
2170 	struct ieee80211_supported_band *sband;
2171 
2172 	if (status->band < 0 ||
2173 	    status->band >= IEEE80211_NUM_BANDS) {
2174 		WARN_ON(1);
2175 		return;
2176 	}
2177 
2178 	sband = local->hw.wiphy->bands[status->band];
2179 
2180 	if (!sband ||
2181 	    status->rate_idx < 0 ||
2182 	    status->rate_idx >= sband->n_bitrates) {
2183 		WARN_ON(1);
2184 		return;
2185 	}
2186 
2187 	rate = &sband->bitrates[status->rate_idx];
2188 
2189 	/*
2190 	 * key references and virtual interfaces are protected using RCU
2191 	 * and this requires that we are in a read-side RCU section during
2192 	 * receive processing
2193 	 */
2194 	rcu_read_lock();
2195 
2196 	/*
2197 	 * Frames with failed FCS/PLCP checksum are not returned,
2198 	 * all other frames are returned without radiotap header
2199 	 * if it was previously present.
2200 	 * Also, frames with less than 16 bytes are dropped.
2201 	 */
2202 	skb = ieee80211_rx_monitor(local, skb, status, rate);
2203 	if (!skb) {
2204 		rcu_read_unlock();
2205 		return;
2206 	}
2207 
2208 	pkt_load = ieee80211_rx_load_stats(local, skb, status, rate);
2209 	local->channel_use_raw += pkt_load;
2210 
2211 	if (!ieee80211_rx_reorder_ampdu(local, skb))
2212 		__ieee80211_rx_handle_packet(hw, skb, status, pkt_load, rate);
2213 
2214 	rcu_read_unlock();
2215 }
2216 EXPORT_SYMBOL(__ieee80211_rx);
2217 
2218 /* This is a version of the rx handler that can be called from hard irq
2219  * context. Post the skb on the queue and schedule the tasklet */
2220 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb,
2221 			  struct ieee80211_rx_status *status)
2222 {
2223 	struct ieee80211_local *local = hw_to_local(hw);
2224 
2225 	BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
2226 
2227 	skb->dev = local->mdev;
2228 	/* copy status into skb->cb for use by tasklet */
2229 	memcpy(skb->cb, status, sizeof(*status));
2230 	skb->pkt_type = IEEE80211_RX_MSG;
2231 	skb_queue_tail(&local->skb_queue, skb);
2232 	tasklet_schedule(&local->tasklet);
2233 }
2234 EXPORT_SYMBOL(ieee80211_rx_irqsafe);
2235